Proceedings
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| Filter results6 paper(s) found. |
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1. Should We Abandon Soil Testing and Yield Goals in Estimating Nitrogen Rates for CornIf the prices of corn and fertilizer-N and the shape of the N response function relating crop yield to the amount of fertilizer used are known, calculating an economically optimal N rate (EONR) for maximizing the net return to applied N is straightforward: the EONR is the N rate at which no firher increase in net return occurs. In most cropping systems and under common price scenarios, crop yield at the EONR is within 95 to 99% of the maximum yield obtained for the specific management package. In... |
2. Nitrogen Loss from Sprinkler Applied Beef Feedlot EffluentLoss of nitrogen from sprinkler applied beef feedlot effluent can be costly for both the producer and the environment. Sprinkler application of effluent is common throughout the Great Plains, though little work has focused specifically on N losses from beef feedlot effluent. We quantified ammonia (NH 3) and nitrous oxide (N2O) losses from beef feedlot effluent applications under field conditions including variations in soil pH, soil water content, ammonium (NH 4+) concentration of the effluent, and... |
3. The Changes in Soil Test Potassium in Kentucky Soils Following Incubation and the Addition of Potassium FertilizerSoil test potassium levels across the state of Kentucky have been declini ng for the past several years. The high price of potash fertilizer has definitely played a role in this decrease, but crop removal rates have also been increasing. This re search is being conducted to improve fertilizer recommendations, to help producers raise or ma intain K soil test level, and to obtain an optimum, profitable yield. Curr ently, University of Kentucky has a single set of K recommendations regardless of soil... |
4. Sidedressed swine manure slurry via dragline hose produces comparable corn grain yields as commercial fertilizersSpring in the upper Midwest can be short and often wet, providing challenges for producers to apply manure and plant crops in a timely manner to maximize yield. As a result, producers apply a significant amount of their manure in the fall after the crop is harvested. Fall applied manure has adequate time to mineralize and leave the root zone before next season’s crop can utilize the nutrients the following summer. These nutrients can end up in rivers and other freshwater bodies, decreasing... C. Pfarr, M. Wilson |
5. Does Sensor-based Nitrogen Management Maintain Crop Production and Decrease Nitrate-N Leaching?To improve water quality, nitrogen (N) management in corn production systems should shift from current N decision support system [maximum return to N (MRTN)] which suggests a single rate N addition to sensor-based (GreenSeeker) active N management (variable N rate approach). Single rate N recommendations often result in under- and over-N addition and either increase environmental N losses or cause corn yield penalty. Our objectives were to evaluate corn optimum nitrogen N requirement (EORN) in... A. Sadeghpour, M. Guzel, J. Mcgrath, O. Adeyemi, B. Arnall, O. Guzel |
6. County-Level Phosphorus Balances for 2017 in IllinoisCropland phosphorus (P) balances (manure and fertilizer P minus crop P removal) are great sustainability tools to assess long-term managements at farm, county, and state levels. Our objectives were to estimate county, regional, and state-level cropland P balances for Illinois in 2017. Based on the census data in 2017, Illinois county P balance ranged from -14.38 to 36 lb/acre/yr. Overall, Illinois had a negative P balance at about -3 lb/acre/yr. About 71% of counties, had a negative P balance,... X. Liu, S. Xu, A. Margenot, A. Sadeghpour, O. Zandvakili, M. Guzel |